JP2003084473A - Device and method for image forming and electrophotographic photoreceptor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the image forming device and the image forming method of an electrophotographic system whose cleaning property is excellent by using the toner of a small grain size and by which the image of a high image quality is obtained and also an electrophotographic photoreceptor used in the image forming device. SOLUTION: The ratio (Dv50/Dp50) of the 50% volume grain size (Dv50) of toner and the 50% number grain size (Dp50) of it is set as 1.0-1.15, and the ratio (Dv75/Dp75) of the cumulative 75% volume grain size (Dv75) of the toner and the cumulative 75% number grain size (Dp75) of it is set as 1.0-1.20, and the number of the toner whose grain size is <=0.7×(Dp50) is set as <=10 number %, and also the electrophotographic photoreceptor possesses an intermediate layer between a conductive substrate and a photoreceptive layer, and the intermediate layer is an insulated layer which incorporates N-type semiconductive particles and binder and in which Bernard cells are formed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic image forming apparatus used in a copying machine or a printer, an image forming method, and an electrophotographic photosensitive member used in the image forming apparatus (hereinafter also simply referred to as a photosensitive member). Regarding

[0002]

2. Description of the Related Art As an electrophotographic image forming method, digital image forming has become the mainstream due to the recent development of digital technology. Digital image forming method is 4
It is basically based on visualizing a small dot image of 1 pixel such as 00 dpi (the number of dots per 2.54 cm), and there is a demand for an image quality improving technique that faithfully reproduces these small dot images.

As one of the techniques for improving the image quality, a toner having a small particle size and a uniform particle size distribution and shape of the toner particles are measured, and an electrophotographic developer using a polymerized toner or an image forming method is proposed. ing. Since the polymerized toner is produced by uniformly dispersing raw material monomers in an aqueous system and then polymerizing the toner, a toner having a uniform particle size distribution and shape can be obtained. However, these small particle size toners have a strong cohesive force between the toners and firmly adhere to the photoconductor, so that the cleaning property is likely to be deteriorated, and cleaning defects such as halftone unevenness, toner filming, and blade curling are poor. Is likely to occur, causing problems that are difficult to put into practical use.

When a toner having a small particle size is used,
It has been pointed out that the color difference between the images at the beginning of development and after running tends to be large.

In digital electrophotographic image formation, a reversal development method is generally used in which image exposure is performed on an image portion and the image exposure portion is visualized by reversal development. In this reversal development, black is used. Image defects called spots tend to occur.

In order to eliminate this black spot, an intermediate layer containing fine particles has been developed. For example, an electrophotographic photosensitive member is known in which an intermediate layer is provided between a conductive support and a photosensitive layer, and titanium oxide particles are dispersed in a resin in the intermediate layer.

Further, a technique relating to an intermediate layer containing surface-treated titanium oxide is also known. For example, iron oxide described in JP-A-4-303846, titanium oxide surface-treated with tungsten oxide, titanium oxide surface-treated with a coupling agent having an amino group described in JP-A-6-96916, and JP-A-9-258469. Oxide surface-treated with an organic silicon compound of JP-A-8-328283
Titanium oxide surface-treated with methyl hydrogen polysiloxane, etc. However, even if these intermediate layers are used, the problem of black spots has not yet been sufficiently solved, and the effect of these intermediate layers for improving the cleaning property of small particle size toner is not described at all. .

It is known that a Benard cell is generated in a coating film to which fine particles and the like are added, but the generation of the Benard cell has been generally treated as being unfavorable.

Regarding the Benard cell, Japanese Patent Laid-Open No. 3-17
No. 962 refers to a method of generating a cell structure (Benard cell) in an undercoat layer to roughen the surface, but there is a description that an image defect occurs because it cannot be controlled. Further, JP-A-8-248651 describes that during the dip coating of the undercoat layer, a Benard cell is generated, the leveling property is deteriorated, and the electrophotographic performance is deteriorated.

On the other hand, the conductive layer and the intermediate layer which positively have the Benard cell are described in JP-A-60-32056 and JP-A-60-252359, but measures against moire have been studied. Nothing is said about the connection with the small particle size toner of the invention.

[0011]

SUMMARY OF THE INVENTION It is an object of the present invention to provide an electrophotographic image forming apparatus and an image forming method which can obtain a high-quality image having a good cleaning property by using a toner having a small particle size. That is to provide an electrophotographic photosensitive member used in the image forming apparatus.

[0012]

The above objects of the present invention have been achieved by the following constitutions.

1. After developing the latent image formed on the electrophotographic photoreceptor with a developer containing toner to visualize the latent image,
In an image forming apparatus that transfers to a recording material and removes residual toner on the electrophotographic photosensitive member by a cleaning unit,
The ratio (Dv50 / Dp50) of the 50% volume particle size (Dv50) and the 50% number particle size (Dp50) of the toner is 1.0.
˜1.15, cumulative 75% volume particle size (Dv75) from the larger volume particle size of the toner, and cumulative 75% number particle size (Dp75) from the larger number particle size of the toner.
Ratio (Dv75 / Dp75) is 1.0 to 1.20, and the particle size is 0.7 × (Dp50) in all toners.
The number of toners below is 10% by number or less, and the electrophotographic photosensitive member has an intermediate layer between the conductive support and the photosensitive layer, and the intermediate layer contains N-type semiconductor particles and a binder. The image forming apparatus is an insulating layer forming a Benard cell.

2. 50% volume particle size (Dv5
0) is 2 μm to 8 μm. The image forming apparatus described in 1 above.

3. 3. The image forming apparatus as described in 1 or 2 above, wherein the toner is obtained from colored particles obtained by polymerizing at least a polymerizable monomer in an aqueous medium.

4. 4. The image forming apparatus described in any one of 1 to 3 above, wherein the toner is obtained from colored particles obtained by salting out / fusing at least resin particles in an aqueous medium.

5. 5. The image forming apparatus described in any one of 1 to 4 above, wherein the toner is a styrene- (meth) acrylate resin.

6. 6. The image forming apparatus described in any one of 1 to 5 above, wherein the N-type semiconductor particles are metal oxide particles.

7. 7. The image forming apparatus as described in 6 above, wherein the metal oxide particles are titanium oxide particles.

8. 7. The titanium oxide particles are subjected to a surface treatment a plurality of times, and the final surface treatment is a surface treatment with a reactive organosilicon compound.
The image forming apparatus according to item 1.

9. 9. The image forming apparatus as described in 8 above, wherein the reactive organosilicon compound is methyl hydrogen polysiloxane.

10. 9. The image forming apparatus as described in 8 above, wherein the reactive organosilicon compound is an organosilicon compound represented by the following general formula (1).

General formula (1) R-Si- (X) ₃ (R represents an alkyl group, an aryl group, X represents a methoxy group, an ethoxy group or a halogen group) 11. 11. The image forming apparatus as described in 10 above, wherein R in the general formula (1) is an alkyl group having 4 to 8 carbon atoms.

12. At least one of the plurality of surface treatments is a surface treatment with one or more compounds selected from alumina, silica, and zirconia. The image forming apparatus described.

13. In any one of the above 7 to 12, wherein the titanium oxide particles are subjected to a surface treatment with silica and / or alumina and then with a reactive organosilicon compound. The image forming apparatus described.

14. 8. The image forming apparatus as described in 7 above, wherein the titanium oxide particles are surface-treated with an organic silicon compound having a fluorine atom.

15. 15. The image forming apparatus as described in any one of 1 to 14 above, wherein the N-type semiconductor particles have a number average primary particle diameter of 10 nm or more and 200 nm or less.

16. 16. The image forming apparatus according to any one of 1 to 15 above, wherein the intermediate layer of the electrophotographic photosensitive member has a thickness of 0.2 to 15 μm.

17. 17. The image forming apparatus according to any one of 1 to 16 above, wherein the binder of the intermediate layer is a polyamide resin.

18. 18. The image forming apparatus according to any one of 1 to 17 above, wherein the cleaning unit has a polyurethane clinching blade.

19. An image forming method using the image forming apparatus according to any one of 1 to 18 above.

20. The electrophotographic photosensitive member used in the image forming apparatus according to any one of 1 to 18 has an intermediate layer between a conductive support and a photosensitive layer, and the intermediate layer includes titanium oxide particles and a binder. An electrophotographic photosensitive member, which is an insulating layer containing the above and forming a Benard cell.

The present invention will be described in detail below. The toner relating to the image forming apparatus of the present invention will be described.

The present inventors have heretofore known an image forming method using a toner having a reduced particle size (in the present invention, a toner having a particle size of 2 μm to 10 μm is referred to as a small particle size toner). As a result of diligent examination of the above problem, it was found that the toner having a reduced particle size tends to have a difference in the developing property and the cleaning property between the particles, and the difference in the adhesive force on the photoconductor tends to increase. .

As a result of investigations, it was found that by forming a Benard cell in the intermediate layer and changing the surface property of the photoconductor, it is possible to reduce the variation difference in the adhesion force of the toner to the photoconductor, and the toner having a reduced particle diameter is found. It has also been found that the developing property can be made uniform and the cleaning property can be improved.

The inventors of the present invention focused on the 50% particle diameter, which is the median value of the toner particle diameters of all toners, rather than merely reducing the existing amount of the small particle diameter component that increases the adhesive force. When analyzing small particle size components that deviate from the particle size, pay attention to the cumulative 75% frequency particle size from the particle size side with the large volume particle size of the toner and the particle size side with the large number particle size. did.

From the above, as described in claim 1, 50% volume particle size (Dv50) and 50% number particle size (Dv) of toner are obtained.
p50) ratio (Dv50 / Dp50) is 1.0 to 1.1.
5. The ratio of the cumulative 75% volume particle size (Dv75) from the larger volume particle size of the toner to the cumulative 75% number particle size (Dp75) from the larger number particle size of the toner (Dp75)
v75 / Dp75) is 1.0 to 1.20, the number of toner particles having a particle size of 0.7 × (Dp50) or less is 10% or less in all toners, and the toner is conductive. By using an electrophotographic photoreceptor having an intermediate layer between a support and a photosensitive layer, the intermediate layer containing N-type semiconductor particles and a binder and having an insulating layer forming a Benard cell, The invention was completed.

The toner according to the present invention (hereinafter, also simply referred to as toner) will be described. First, the volume particle diameter, the number particle diameter, and the ratio of the volume particle diameter to the number particle diameter of the toner according to the present invention will be described.

From the viewpoint of obtaining the effects described in the present invention, the toner according to the present invention is preferably monodisperse in particle size distribution, and has a 50% volume particle diameter (Dv50) and a 50% number particle diameter (Dp50). Ratio (Dv50 / Dp50) is 1.0 to
It must be 1.15, but is preferably 1.0
Is about 1.13.

In order to suppress the fluctuation range of transferability and developability, the ratio (Dv75) of the cumulative 75% volume particle diameter (Dv75) and the 75% number particle diameter (Dp75) from the larger toner is used.
75 / Dp75) is required to be 1.0 to 1.20, preferably 1.1 to 1.19. Further, in all toners, the particle size is 0.7 × (Dp50)
The number of toners below is required to be 10% by number or less, but preferably 5% by number to 9% by number.

The 50% volume particle size (D
v50) is preferably 2 μm to 8 μm, and more preferably 3 μm to 7 μm. The 50% number particle size (Dp50) of the toner according to the present invention is preferably 2 μm to 7.5 μm, and more preferably 2.5 μm to 7 μm. By setting it in this range, the effect of the present invention can be more remarkably exhibited.

Here, cumulative 75% volume particle size (Dv75) or cumulative 75% number particle size (Dp75) from the larger one.
Is expressed as the volume particle size or the number particle size of the particle size distribution region in which the frequencies from the larger particle size are accumulated, and each shows 75% of the sum of the total volume or the sum of the number.

In the present invention, 50% volume particle size (Dv5
0), 50% number particle size (Dp50), cumulative 75% volume particle size (Dv75), cumulative 75% number particle size (Dp75), etc., with a Coulter Counter TA-II type or Coulter Multisizer (manufactured by Coulter) It can be measured.

The photosensitive member has an intermediate layer between the conductive support and the photosensitive layer, and the intermediate layer contains an N-type semiconductor particle and a binder, and has an insulating layer forming a Benard cell. By using such an intermediate layer, minute irregularities are generated on the surface of the photoconductor, the adhesion force of the toner onto the photoconductor is reduced, and a remarkable effect is exerted on the developability and the cleaning property. That is, it is important to sufficiently form the Benard cell structure in the intermediate layer and change the surface property of the photoconductor.

The constituents of the toner according to the present invention, the constituents of the binder resin which is a constituent of the toner, and the production thereof will be described.

The toner according to the present invention contains at least a colorant, a binder resin and the like, but the toner may be manufactured through a crushing / classifying process, and a polymerizable monomer as shown below is polymerized. It may be produced by a so-called polymerization method in which a toner is produced using the resin particles obtained in this way. When a toner is manufactured by using a polymerization method, a manufacturing method having a step of salting out / fusing resin particles is particularly preferable.

As the polymerizable monomer used in the polymerization method, a radical polymerizable monomer may be used as a constituent component, and a crosslinking agent may be used if necessary. Further, it is preferable to contain at least one radical-polymerizable monomer having the following acidic group or radical-polymerizable monomer having a basic group.

(1) Radical Polymerizable Monomer The radical polymerizable monomer component is not particularly limited, and conventionally known radical polymerizable monomers can be used. Also, in order to satisfy the required characteristics, 1
One kind or a combination of two or more kinds can be used.

Specifically, aromatic vinyl monomers, (meth) acrylic acid ester monomers, vinyl ester monomers, vinyl ether monomers, monoolefin monomers, diolefin monomers. Examples thereof include monomers and halogenated olefin-based monomers.

As the aromatic vinyl monomer, for example,
Styrene, o-methylstyrene, m-methylstyrene,
p-methylstyrene, p-methoxystyrene, p-phenylstyrene, p-chlorostyrene, p-ethylstyrene, p-n-butylstyrene, p-tert-butylstyrene, p-n-hexylstyrene, p-n- Examples thereof include styrene-based monomers such as octylstyrene, pn-nonylstyrene, pn-decylstyrene, pn-dodecylstyrene, 2,4-dimethylstyrene, and 3,4-dichlorostyrene, and derivatives thereof. .

Examples of the (meth) acrylic acid ester-based monomer include methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, phenyl acrylate, methyl methacrylate, ethyl methacrylate. , Butyl methacrylate, hexyl methacrylate, 2-ethylhexyl methacrylate, ethyl β-hydroxyacrylate, γ-aminoacrylate propyl, stearyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate and the like.

Examples of vinyl ester monomers include vinyl acetate, vinyl propionate and vinyl benzoate.

Examples of vinyl ether type monomers include vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether, vinyl phenyl ether and the like.

Examples of the monoolefin-based monomer include ethylene, propylene, isobutylene, 1-butene, 1-pentene, 4-methyl-1-pentene and the like.

Examples of the diolefin-based monomer include butadiene, isoprene, chloroprene and the like.

As the halogenated olefin-based monomer,
Examples thereof include vinyl chloride, vinylidene chloride, vinyl bromide and the like.

(2) Crosslinking agent As a crosslinking agent, a radically polymerizable crosslinking agent may be added to improve the characteristics of the toner. Radical polymerizable cross-linking agents include divinylbenzene, divinylnaphthalene,
Examples thereof include those having two or more unsaturated bonds such as divinyl ether, diethylene glycol methacrylate, ethylene glycol dimethacrylate, polyethylene glycol dimethacrylate and diallyl phthalate.

(3) Radical-polymerizable monomer having an acidic group or radical-polymerizable monomer having a basic group Radical-polymerizable monomer having an acidic group or radical-polymerizable monomer having a basic group Examples of the amine-based compound include a polymerizable monomer having a carboxyl group, a polymerizable monomer having a sulfonic acid group, a primary amine, a secondary amine, a tertiary amine, and a quaternary ammonium salt. The polymerizable monomer of is mentioned.

Examples of the polymerizable monomer having a carboxyl group include acrylic acid, methacrylic acid, fumaric acid, maleic acid, itaconic acid, cinnamic acid, maleic acid monobutyl ester and maleic acid monooctyl ester.

Examples of the polymerizable monomer having a sulfonic acid group include styrenesulfonic acid, allylsulfosuccinic acid and octyl allylsulfosuccinate.

These may have a structure of an alkali metal salt such as sodium or potassium or an alkaline earth metal salt such as calcium.

Examples of the radical polymerizable monomer having a basic group include amine compounds, such as dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, diethylaminoethyl acrylate, diethylaminoethyl methacrylate, and quaternary compounds of the above four compounds. Ammonium salt, 3-dimethylaminophenyl acrylate, 2-hydroxy-3-methacryloxypropyltrimethylammonium salt, acrylamide, N-butylacrylamide, N, N-dibutylacrylamide,
Piperidyl acrylamide, methacrylamide, N-butyl methacrylamide, N-octadecyl acrylamide; vinyl pyridine, vinyl pyrrolidone; vinyl N-methylpyridinium chloride, vinyl N-ethylpyridinium chloride, N, N-diallylmethylammonium chloride, N, N- Examples include diallylethylammonium chloride.

As the radical-polymerizable monomer used in the present invention, a radical-polymerizable monomer having an acidic group or a radical-polymerizable monomer having a basic group is contained in an amount of 0.1 to 15 of all monomers. The radical-polymerizable cross-linking agent is preferably used in an amount of 0.1 to 10 mass% with respect to the total radical-polymerizable monomers, although it depends on its characteristics.

[Chain Transfer Agent] A commonly used chain transfer agent can be used for the purpose of adjusting the molecular weight. The chain transfer agent is not particularly limited, and examples thereof include octyl mercaptan, dodecyl mercaptan, tert-dodecyl mercaptan, n-octyl-3-mercaptopropionic acid ester, carbon tetrabromide and styrene dimer.

[Polymerization Initiator] The radical polymerization initiator used in the present invention can be appropriately used if it is water-soluble.
For example, persulfates (potassium persulfate, ammonium persulfate, etc.), azo compounds (4,4′-azobis-4-cyanovaleric acid and its salts, 2,2′-azobis (2-amidinopropane) salt, etc.), peroxides A compound etc. are mentioned.

Further, the above radical polymerization initiator can be used as a redox initiator in combination with a reducing agent, if necessary. By using the redox type initiator, the polymerization activity can be increased, the polymerization temperature can be lowered, and further shortening of the polymerization time can be expected.

As the polymerization temperature, any temperature may be selected as long as it is at least the minimum radical generation temperature of the polymerization initiator, but for example, a range of 50 ° C. to 90 ° C. is used. However, it is also possible to polymerize at room temperature or higher by using a combination of a polymerization initiator that starts at room temperature, for example, a combination of hydrogen peroxide and a reducing agent (ascorbic acid, etc.).

[Surfactant] In order to carry out polymerization using the above-mentioned radically polymerizable monomer, it is necessary to disperse oil droplets in an aqueous medium using a surfactant. The surfactant that can be used in this case is not particularly limited, but the following ionic surfactants can be mentioned as suitable examples.

As the ionic surfactant, sulfonates (sodium dodecylbenzene sulfonate, sodium arylalkyl polyether sulfonate, 3,3-
Disulfone diphenylurea-4,4-diazo-bis-amino-8-naphthol-6-sulfonate sodium, ortho-carboxybenzene-azo-dimethylaniline,
2,2,5,5-tetramethyl-triphenylmethane-
4,4-diazo-bis-β-naphthol-6-sulfonate, etc.), sulfuric acid ester salts (sodium dodecyl sulfate, sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate, etc.), fatty acid salts (sodium oleate, laurin) Acid sodium salt, sodium caprate, sodium caprylate, sodium caproate, potassium stearate, calcium oleate and the like).

Further, nonionic surfactants can also be used. Specifically, polyethylene oxide, polypropylene oxide, a combination of polypropylene oxide and polyethylene oxide, ester of polyethylene glycol and higher fatty acid, alkylphenol polyethylene oxide, ester of higher fatty acid and polyethylene glycol, ester of higher fatty acid and polypropylene oxide, sorbitan ester. Etc. can be given.

In the present invention, these are mainly used as an emulsifier during emulsion polymerization, but they may be used for other steps or purposes.

[Colorant] Examples of the colorant include inorganic pigments, organic pigments and dyes.

As the inorganic pigment, conventionally known ones can be used. Specific inorganic pigments are exemplified below.

Examples of black pigments include furnace black, channel black, acetylene black,
Carbon black such as thermal black and lamp black, and magnetic powder such as magnetite and ferrite are also used.

These inorganic pigments can be used alone or in combination of two or more as desired. Further, the amount of the pigment added is 2 to 20% by mass, preferably 3 to 15% by mass, based on the polymer.

When used as a magnetic toner, the above-mentioned magnetite can be added. In this case, from the viewpoint of imparting a predetermined magnetic characteristic, 20 to 6 is contained in the toner.
It is preferable to add 0% by mass.

Known organic pigments and dyes can be used. Specific organic pigments and dyes are exemplified below.

As the magenta or red pigment,
C. I. Pigment Red 2, C.I. I. Pigment Red 3, C.I. I. Pigment Red 5, C.I. I. Pigment Red 6, C.I. I. Pigment Red 7, C.I. I. Pigment Red 15, C.I. I. Pigment Red 16,
C. I. Pigment Red 48: 1, C.I. I. Pigment Red 53: 1, C.I. I. Pigment Red 57:
1, C.I. I. Pigment Red 122, C.I. I. Pigment Red 123, C.I. I. Pigment Red 139,
C. I. Pigment Red 144, C.I. I. Pigment Red 149, C.I. I. Pigment Red 166, C.I.
I. Pigment Red 177, C.I. I. Pigment Red 178, C.I. I. Pigment Red 222 and the like.

Pigments for orange or yellow include C.I. I. Pigment Orange 31, C.I. I. Pigment Orange 43, C.I. I. Pigment Yellow 12,
C. I. Pigment Yellow 13, C.I. I. Pigment Yellow 14, C.I. I. Pigment Yellow 15, C.I.
I. Pigment Yellow 17, C.I. I. Pigment Yellow 93, C.I. I. Pigment Yellow 94, C.I. I.
Pigment Yellow 138, C.I. I. Pigment Yellow 180, C.I. I. Pigment Yellow 185, C.I.
I. Pigment Yellow 155, C.I. I. Pigment Yellow 156 and the like.

As a pigment for green or cyan,
C. I. Pigment Blue 15, C.I. I. Pigment Blue 15: 2, C.I. I. Pigment Blue 15: 3,
C. I. Pigment Blue 16, C.I. I. Pigment Blue 60, C.I. I. Pigment Green 7 and the like.

As the dye, C.I. I. Solvent Red 1, 49, 52, 58, 63, 111,
122, C.I. I. Solvent Yellow 19, 44,
77, 79, 81, 82, 93, 98, 103, 104, 112, 162, C.I. I. Solvent Blue 25, 36, 60, 70, 93,
Id. 95 and the like can be used, and a mixture thereof can also be used.

These organic pigments and dyes can be used alone or in combination of two or more as desired. Further, the amount of the pigment added is 2 to 20% by mass, preferably 3 to 15% by mass, based on the polymer.

The colorant may be surface-modified before use. As the surface modifier, conventionally known ones can be used, and specifically, a silane coupling agent, a titanium coupling agent, an aluminum coupling agent and the like can be preferably used.

The toner according to the present invention may be used in combination with a release agent, for example, low molecular weight polyolefin wax such as polypropylene and polyethylene, paraffin wax,
Fischer-Tropsch wax, ester wax and the like can be used as a release agent. Further, in the present invention, the ester wax represented by the following general formula (1) can be preferably used.

In the general formula (1) R _1- (OCO-R ₂ ) _n formula, n represents an integer of 1 to 4, preferably 2 to 4, more preferably 3 to 4, and particularly preferably. It is 4.

R ₁ and R ₂ represent a hydrocarbon group which may have a substituent. R _1: a carbon number = 1-40, preferably 1-20, more preferably 2 to 5 R _2: the number of carbon atoms = 1-40, preferably 13-29, more preferably to 12 to 25 below, the present invention Specific examples of the crystalline compound having such an ester group are shown below, but the present invention is not limited thereto.

[0087]

[Chemical 1]

[0088]

[Chemical 2]

These ester waxes are contained in the resin particles and have the function of imparting good fixability (adhesiveness to the image support) to the toner obtained by fusing the resin particles.

The amount of the release agent used in the present invention is preferably 1% by mass to 30% by mass, more preferably 2% by mass to 20% by mass, and further preferably 3% by mass based on the total amount of the toner.
Is about 15% by mass. Further, the toner of the present invention is prepared by dispersing the above-mentioned releasing agent in the above-mentioned polymerizable monomer in water and polymerizing it to form an ester compound as a releasing agent in the resin particles. A toner produced through a step of forming particles encapsulating the above and salting out / fusing with the colorant particles is preferable.

In the toner according to the present invention, a material capable of imparting various functions as a toner material may be added in addition to the colorant and the release agent. Specific examples include charge control agents. These components can be added by various methods such as a method of adding the resin particles and the colorant particles at the same time as the salting-out / fusing step and incorporating them into the toner, a method of adding them to the resin particles themselves.

Similarly, various charge control agents are known,
Moreover, the thing which can be disperse | distributed in water can be used. Specifically, nigrosine dyes, metal salts of naphthenic acid or higher fatty acids, alkoxylated amines,
Examples thereof include secondary ammonium salt compounds, azo-based metal complexes, salicylic acid metal salts or metal complexes thereof.

External additives used in the toner according to the present invention will be described. The toner according to the present invention, for the purpose of improving fluidity, chargeability and cleaning property,
So-called external additives can be added and used. Although these external additives are not particularly limited, various inorganic fine particles, organic fine particles and lubricants can be used.

As the inorganic fine particles, conventionally known ones can be used. Specifically, silica, titanium, alumina fine particles and the like can be preferably used. The inorganic fine particles are preferably hydrophobic. Specifically, as the silica fine particles, for example, commercially available products R-805, R-976, R-974, and R-97 manufactured by Nippon Aerosil Co., Ltd.
2, R-812, R-809, Hovst HVK-
2150, H-200, commercial product TS- manufactured by Cabot Corporation
720, TS-530, TS-610, H-5, MS-
5 and the like.

Examples of titanium fine particles include commercial products T-805 and T-604 manufactured by Nippon Aerosil Co., Ltd., and commercial products MT-100S, MT-100B and MT-5 manufactured by Teika.
00BS, MT-600, MT-600SS, JA-
1. Commercial products TA-300SI and TA- manufactured by Fuji Titanium Co., Ltd.
500, TAF-130, TAF-510, TAF-5
10T, commercial products IT-S, IT-OA manufactured by Idemitsu Kosan Co., Ltd.
IT-OB, IT-OC, etc. are mentioned.

Examples of the alumina fine particles include commercial products RFY-C and C-604 manufactured by Nippon Aerosil Co., Ltd. and commercial product TTO-55 manufactured by Ishihara Sangyo Co., Ltd.

As the organic fine particles, spherical organic fine particles having a number average primary particle diameter of about 10 to 2000 nm can be used. As this, a homopolymer such as styrene or methyl methacrylate or a copolymer thereof can be used.

Examples of the lubricant include zinc stearate, aluminum, copper, magnesium, calcium salts, oleic acid zinc, manganese, iron, copper, magnesium salts, and palmitic acid zinc, copper, magnesium, calcium. And the like, salts of zinc and calcium of linoleic acid, and metal salts of higher fatty acids such as salts of zinc and calcium of ricinoleic acid.

The addition amount of these external additives is preferably 0.1 to 5 mass% with respect to the toner. Examples of the method of adding the external additive include various known mixing devices such as a Turbuler mixer, a Henschel mixer, a Nauter mixer, and a V-type mixer.

A method of manufacturing the electrostatic charge image developing toner according to the present invention will be described. << Manufacturing Step >> The toner of the present invention has a release agent dissolved therein, the polymerizable monomer or the polymerizable monomer solution as described above is dispersed in an aqueous medium, and then the release agent is encapsulated by a polymerization method. A step of adjusting the resin particles, a step of fusing the resin particles in an aqueous medium using the resin particle dispersion, a washing step of filtering the obtained particles from the aqueous medium to remove a surfactant, etc. It is preferable to manufacture by a polymerization method including a step of drying the obtained particles and an external additive addition step of adding an external additive or the like to the particles obtained by further drying. Here, the resin particles may be colored particles. In addition, non-colored particles can also be used as the resin particles. In this case, the colored particles are obtained by adding the colorant particle dispersion liquid or the like to the dispersion liquid of the resin particles and then fusing in an aqueous medium. You can

Particularly, as the fusion method, a method of salting out / fusing by using the resin particles produced in the polymerization step is preferable. When non-colored resin particles are used, the resin particles and the colorant particles can be salted out / fused in an aqueous medium.

Further, not only the colorant and the release agent, but also the charge control agent which is a constituent element of the toner can be added as particles in this step.

Here, the aqueous medium means one containing water as a main component and having a water content of 50% by mass or more. Examples of substances other than water include organic solvents that dissolve in water, such as methanol, ethanol, isopropanol, butanol, acetone, methyl ethyl ketone, and tetrahydrofuran. It is preferably an organic solvent that does not dissolve the resin,
Alcohol-based organic solvents such as methanol, ethanol, isopropanol and butanol are particularly preferable.

As a preferable polymerization method in the present invention, a monomer solution in which a releasing agent is dissolved in a monomer is dispersed by mechanical energy into oil droplets in an aqueous medium in which a surfactant having a concentration below the critical micelle concentration is dissolved. A method in which a water-soluble polymerization initiator is added to the dispersion to carry out radical polymerization can be mentioned. In this case, an oil-soluble polymerization initiator may be added to the monomer before use.

The disperser for dispersing the oil droplets is not particularly limited, and examples thereof include Clearmix, an ultrasonic disperser, a mechanical homogenizer, a Manton-Gaulin, a pressure homogenizer and the like.

The colorant itself may be surface-modified before use. The surface modification method of the colorant involves dispersing the colorant in a solvent,
After the surface modifier is added therein, the temperature is raised to carry out the reaction. After completion of the reaction, the pigment is filtered, washed and filtered with the same solvent repeatedly, and dried to obtain a pigment treated with a surface modifier.

The colorant particles may be prepared by dispersing the colorant in an aqueous medium. This dispersion is preferably carried out in water with the surfactant concentration being equal to or higher than the critical micelle concentration (CMC).

The disperser at the time of dispersing the pigment is not particularly limited, but preferably Clearmix, ultrasonic disperser, mechanical homogenizer, pressure disperser such as Manton-Gorin or pressure homogenizer, sand grinder, Getzmann mill or diamond fine mill. And the like medium-type dispersers.

As the surfactant used here, the above-mentioned surfactants can be used. In the salting-out / fusing step, a salting-out agent composed of an alkali metal salt, an alkaline earth metal salt or the like is added as a flocculant having a critical coagulation concentration or higher in water in which the resin particles and the colorant particles are present. Then, it is a step of heating the resin particles to a temperature not lower than the glass transition point thereof to promote salting-out and at the same time perform fusion.

Examples of the alkali metal salts and alkaline earth metal salts which are salting-out agents include lithium, potassium, sodium and the like as alkali metals, and magnesium, calcium, strontium, barium and the like as alkaline earth metals. And preferably potassium, sodium, magnesium, calcium, or barium. Examples of the salt include chlorine salt, bromine salt, iodine salt, carbonate salt, and sulfate salt.

The method for achieving the particle size distribution of the toner is not particularly limited, but for example, control by a method such as classification, temperature and time at the time of association, and control of a stopping method for ending the association can be performed. Techniques can be used.

As a particularly preferred production method, a method of controlling the association time in water, the association temperature, the stopping speed, etc. can be mentioned. That is, in the case of salting out / fusing, it is preferable that the time after leaving the salting out agent is left as short as possible. Although it is not clear as the reason for this, the agglomeration state of the particles varies depending on the standing time after salting out,
There arise problems that the particle size distribution becomes unstable and the surface property of the fused toner changes. The temperature at which the salting-out agent is added is not particularly limited.

In the present invention, it is preferable to use a method of raising the temperature of the dispersion liquid of the resin particles as quickly as possible and heating it to the glass transition temperature of the resin particles or higher. The time required to raise the temperature is less than 30 minutes, preferably less than 10 minutes. Further, although it is necessary to raise the temperature quickly, the rate of temperature increase is preferably 1 ° C./minute or more. Although the upper limit is not particularly clear, it is preferably 15 ° C./min or less from the viewpoint of suppressing the generation of coarse particles due to the rapid progress of salting out / fusion. As a particularly preferable form, a method of continuously advancing salting out / fusion even at the time of reaching the glass transition temperature or higher can be mentioned. By using this method, it is possible to effectively promote fusion with the growth of particles, and improve the durability as a final toner.

Further, it is possible to particularly control the particle size by salting out / fusing with a divalent metal salt at the time of association. The reason for this is not clear, but the use of a divalent metal salt increases the repulsive force during salting-out, which makes it possible to effectively suppress the dispersibility of the surfactant, and as a result, the exile distribution It is presumed that it became possible to control.

Further, it is preferable to add a monovalent metal salt and water in order to stop salting out / fusion. By adding this, salting out can be stopped, and as a result, it becomes possible to suppress the presence of a large particle size component or a small particle size component.

In the case of a polymerized toner in which resin particles are associated or fused in an aqueous medium, the flow and temperature distribution of the medium in the reaction vessel at the fusion stage are controlled, and the shape control step after the fusion is performed. By controlling the heating temperature, the rotation number of stirring, and the time, the shape distribution and shape of the entire toner can be arbitrarily changed.

That is, in the case of a polymerization toner in which resin particles are associated or fused, the flow in the reaction device is laminar flow,
By using a stirring blade and a stirring tank capable of making the internal temperature distribution uniform, by controlling the temperature, the number of rotations, and the time in the fusion process and the shape control process, the shape factor and uniformity of the present invention A toner having a shape distribution can be formed. The reason for this is that when fusion is performed in a laminar flow-forming place, strong stress is not applied to particles (association or agglomerated particles) in which aggregation and fusion are progressing, and in a laminar flow in which the flow is accelerated, As a result of the uniform temperature distribution in the stirring tank, it is estimated that the shape distribution of the fused particles becomes uniform. Further, the fused particles are gradually made spherical by heating and stirring in the subsequent shape control step, and the shape of the toner particles can be arbitrarily controlled.

In order to control the toner of the present invention to have a predetermined shape, it is preferable to carry out salting out and fusion at the same time.
The method of heating after forming the agglomerated particles tends to cause a distribution in the shape thereof, and cannot suppress the generation of fine particles. That is, it is presumed that since the aggregated particles are heated in an aqueous medium while being stirred, reaggregation of the aggregated particles occurs, and a component having a small particle size is likely to occur.

The developer used in the present invention will be described. When mixed with a carrier and used as a two-component developer, iron, ferrite,
Metals such as magnetite, those metals and aluminum,
A conventionally known material such as an alloy with a metal such as lead can be used. Ferrite particles are particularly preferable. The magnetic particles have a volume average particle diameter of 15 to 100 μm,
It is more preferably 25 to 80 μm.

The volume average particle diameter of the carrier is typically measured by a laser diffraction type particle size distribution measuring apparatus "HELOS" equipped with a wet disperser (SYMPATIC (SYMP).
(Made by ATEC)).

The carrier is preferably one in which magnetic particles are further coated with a resin, or a so-called resin dispersion type carrier in which magnetic particles are dispersed in a resin. The resin composition for coating is not particularly limited, but, for example, an olefin resin, a styrene resin, a styrene-acrylic resin, a silicone resin, an ester resin, a fluorine-containing polymer resin, or the like is used. The resin for forming the resin-dispersed carrier is not particularly limited, and known ones can be used. For example, styrene-acrylic resin, polyester resin, fluorine resin, phenol resin, etc. are used. be able to.

The electrophotographic photosensitive member according to the present invention will be described. The present inventors currently hold the following assumptions regarding the relation of an insulating layer having a Benard cell structure, which is one of the features of the present invention.

That is, the insulating layer having the Benard cell structure has a state in which the layer between the adjacent layers is eroded by the unevenness of the surface of the cell, and the N-type semiconductor particles are contained in this state. Electrical compatibility is improved,
It is presumed that the electrophotographic characteristics, especially the chargeability upon repetition are improved, and the adhesiveness is improved.

Further, a toner having stable chargeability is preferably used, and therefore, a toner having a uniform particle size is preferable. As one method for this purpose, a polymerized toner prepared by a polymerization method is substantially spherical and has a surface property. It was found to be preferable because it was uniform.

However, the toner has a drawback that black spots are likely to occur frequently, the amount of wear of the photosensitive layer is large, and the peeling from the edge tends to be increased. However, by using the toner according to the present invention, It was possible to obtain favorable results for these as well.

The Benard cell according to the present invention is generated in a coating layer when the coating layer is formed, as disclosed in JP-A-6-155313 and JP-A-60-32056. It is synonymous with "benard cell (convection cell) phenomenon".

That is, when the dispersion liquid for forming the intermediate layer and the like is applied to form the coating layer, the components in the coating layer are added to the coating layer in the process of drying and solidifying to form the coating layer. It is generated by causing convection in the vertical direction and applying surface tension to it.

The inventors of the present invention utilize the “Benard cell (convection cell) phenomenon” occurring in the coating layer to obtain an intermediate layer, and by forming a Benard cell on the surface of the intermediate layer, the black spot disappears. And succeeded in improving the adhesiveness.

The Benard cell structure according to the present invention (hereinafter sometimes simply referred to as a Benard cell) means that it has a polygonal shape or a partially polygonal shape when observed from the surface side, It preferably has a hexagonal shape. Among polygons, the proportion of hexagons is preferably 10 to 100% (on a number basis), preferably 2
0-100% is good.

The size of the Benard cell according to the present invention is preferably about 10 to 500 μm at the longest part.

The size and depth of the Benard cell in the intermediate layer according to the present invention can be controlled by appropriately adjusting the viscosity, surface tension, solvent composition and type of the intermediate layer dispersion, coating amount, film thickness, drying conditions and the like. It can be carried out by selecting, for example, when the viscosity is adjusted to be in the range of 7 × 10 ⁻³ to 250 × 10 ⁻³ Pa · s, it is preferable. Titanium oxide is relatively easy to generate.

When the dispersion has a high viscosity exceeding the above range or a low viscosity below the lower limit, the solvent contained in the coating layer evaporates and the coating layer is solidified. No convection of the dispersion liquid in the coating layer occurs, or the degree of convection is too low, and thus the dispersion liquid may not be formed.

The film thickness of the intermediate layer according to the present invention is preferably 0.2 to 15 μm and coated and dried as described above, more preferably 0.3 to 10 μm, and further 0.5 to.
8 μm is preferable.

If the film thickness is less than 0.2 μm, the solvent contained in the coating layer evaporates and the coating layer becomes a convective driving force of convection generated in the process of solidifying the coating layer. The difference in the surface tension and the difference in the buoyancy between the upper and lower surfaces of the layer are not significant, making it difficult to form cells on the surface. Also, the film thickness 15
If it is larger than μm, in the drying step of the coating layer, the solvent inside the coating layer evaporates due to forced drying even after the surface of the coating layer is solidified, foaming or cracking occurs in the layer, and it is difficult to form uniformly on the surface. Become.

The electrophotographic photoreceptor of the present invention comprises an intermediate layer provided between a conductive substrate or a conductive support and a photosensitive layer, and the intermediate layer further contains N-type semiconductor particles.

The above-mentioned particles according to the present invention preferably have a number average primary particle diameter in the range of 10 nm to 200 nm, more preferably 15 nm to 150 nm.

If the particle size is less than 10 nm, no Benard cell is generated in the intermediate layer, and the effect of preventing black spots from being generated by the intermediate layer is small. On the other hand, if it is larger than 200 nm, the uniformity of the Benard cell is poor, and as a result, black spots also increase. An intermediate layer coating solution using N-type semiconductive particles having a number average primary particle size in the above range has good dispersion stability, and an intermediate layer formed from such a coating solution having a Benard cell is a black spot. In addition to the function of preventing generation, it has good environmental characteristics and has cracking resistance.

The number average primary particle size of the N-type semiconductor particles is
For example, in the case of titanium oxide, it is a measurement value as a Feret direction average diameter obtained by observing 100 particles as primary particles randomly by enlarging by 10,000 times by observation with a transmission electron microscope.

Specific examples of the N-type semiconductor particles according to the present invention include metal oxide particles such as titanium oxide (TiO ₂ ), zinc oxide (ZnO) and tin oxide (SnO ₂ ).
Among them, titanium oxide is preferable, and further, N-type semiconductor particles subjected to surface treatment for achieving good dispersibility are preferable. Titanium oxide particles that have been surface-treated are particularly preferable. The content ratio of particles in the intermediate layer is 10 in terms of volume ratio.
% To 90% is preferable, and 25% to 75% is more preferable.

Here, the N-type semiconductor particles are fine particles having a property of making conductive carriers electrons. That is,
The property that the conductive carriers are electrons means that the N-type semiconductor particles are contained in an insulating binder to efficiently block hole injection from the substrate and block electrons from the photosensitive layer. It has a property that does not show sex.

The surface treatment of the N-type semiconductor particles is preferably performed by coating the surface of the N-type semiconductor particles with a metal oxide, a reactive organosilicon compound, an organometallic compound or the like. Examples of preferable surface treatment of N-type semiconductor particles used in the present invention are described below.

One of the preferable surface treatments for N-type semiconductor particles is as follows. That is, the surface treatment is performed a plurality of times, and the last surface treatment among the plurality of surface treatments is the surface treatment with the reactive organosilicon compound.

Another preferred surface treatment of N-type semiconductor particles is surface treatment with methylhydrogenpolysiloxane.

Another preferred surface treatment of N-type semiconductor particles is surface treatment with an organic silicon compound having a fluorine atom. In this case, the surface treatment may be carried out plural times, and the final treatment may be carried out with the organosilicon compound having the fluorine atom.

By providing the intermediate layer according to the present invention between the conductive support and the photosensitive layer by containing the N-type semiconductor particles which have been subjected to the above surface treatment, electrophotography of residual potential, charging potential, etc. The generation of black spots can be significantly suppressed without deteriorating the characteristics, and the generation of moire due to laser exposure can be improved.

The titanium oxide particles preferably used in the present invention have a number average primary particle diameter of 10 nm or more and 200 n or less.
The range of m or less is preferable. An intermediate layer coating solution using titanium oxide particles having a number average primary particle size in the above range has good dispersion stability, and an intermediate layer formed from such a coating solution has a sufficient black spot generation preventing function.

The shape of the titanium oxide particles is dendritic, acicular, granular or the like, and the titanium oxide having such a shape has anatase type, rutile type or amorphous type as the crystal type. However, any shape and crystal type may be used, and two or more shapes and crystal types may be mixed and used.

Surface treatment performed on the N-type semiconductor particles of the present invention
One of the reasons is that it is preferable to perform the surface treatment multiple times,
And the last surface treatment in the plurality of surface treatments is a reaction
It is preferable to perform surface treatment with a hydrophilic organosilicon compound.
Yes. In addition, at least once in the plurality of surface treatments
The surface treatment of alumina (Al₂O₃), Silica (Si
O ₂), And zirconia (ZrO₂) Less selected from
Both are done with one or more compounds, and finally reactive
To be surface treated with an organosilicon compound
Is preferred. Note that these compounds also have hydrates.
Also included.

Further, as another method of the surface treatment applied to the N-type semiconductor particles of the present invention, the surface treatment is performed a plurality of times, and the last surface treatment among the plurality of surface treatments is performed. It is preferable to perform surface treatment using a reactive organic titanium compound or a reactive organic zirconium compound. Further, among the plurality of surface treatments, at least one surface treatment is performed using at least one compound selected from alumina, silica, and zirconia as described above, and finally, a reactive organotitanium compound or It is preferable to perform surface treatment with a reactive organozirconium compound.

Thus, the surface treatment of the N-type semiconductor particles such as titanium oxide particles is performed at least twice, so that the surface of the N-type semiconductor particles is uniformly coated (treated), and the N-treated surface is treated. When the type semiconductor particles are used in the intermediate layer according to the present invention, a good photoreceptor having good dispersibility of N type semiconductor particles such as titanium oxide particles in the intermediate layer and not causing image defects such as black spots is obtained. It is possible and preferable.

In addition, the surface treatment is performed a plurality of times by using alumina and silica, and then the surface treatment is performed by using a reactive organosilicon compound, or the surface treatment is performed by using alumina and silica and then the reactive organic compound is used. Those which are surface-treated with a titanium compound or a reactive organic zirconium compound are particularly preferable.

The above-mentioned treatment of alumina and silica may be carried out at the same time, but especially the treatment of alumina is first carried out,
Next, it is preferable to perform silica treatment. Further, the treatment amount of alumina and silica in the case of performing treatment of alumina and silica is preferably such that the amount of silica is larger than that of alumina.

The surface treatment of the N-type semiconductor particles such as titanium oxide described above with a metal oxide such as alumina, silica and zirconia can be carried out by a wet method. For example, silica,
Alternatively, the N-type semiconductor particles that have been subjected to the surface treatment of alumina can be manufactured as follows.

When titanium oxide particles are used as the N-type semiconductor particles, titanium oxide particles (number average primary particle diameter: 50 n
m) is dispersed in water at a concentration of 50 to 350 g / L to give an aqueous slurry, to which a water-soluble silicate or a water-soluble aluminum compound is added. Then, neutralize by adding an alkali or an acid, silica on the surface of the titanium oxide particles,
Alternatively, alumina is precipitated. Subsequently, filtration, washing and drying are performed to obtain the target surface-treated titanium oxide. When sodium silicate is used as the water-soluble silicate, it can be neutralized with an acid such as sulfuric acid, nitric acid or hydrochloric acid. on the other hand,
When aluminum sulfate is used as the water-soluble aluminum compound, it can be neutralized with an alkali such as sodium hydroxide or potassium hydroxide.

The amount of the metal oxide used in the surface treatment is 0.1 to 5 with respect to 100 parts by mass of N-type semiconductor particles such as titanium oxide particles in the charged amount during the surface treatment.
0 parts by mass, more preferably 1 to 10 parts by mass of metal oxide is preferably used. Even when the above-mentioned alumina and silica are used, for example, in the case of titanium oxide particles, it is preferable to use 1 to 10 parts by mass with respect to 100 parts by mass of titanium oxide particles, and the amount of silica is larger than that of alumina. preferable.

The surface treatment with the reactive organic silicon compound, which is performed after the surface treatment with the metal oxide, is preferably performed by the following wet method.

That is, the titanium oxide treated with the metal oxide is added to a solution prepared by dissolving or suspending the reactive organosilicon compound in an organic solvent or water, and the solution is stirred for a few minutes to 1 hour. To do. Then, in some cases, the liquid is subjected to a heat treatment, subjected to a process such as filtration and then dried to obtain titanium oxide particles whose surface is coated with an organosilicon compound. The reactive organic silicon compound may be added to a suspension of titanium oxide dispersed in an organic solvent or water.

In the present invention, the surface of titanium oxide particles is coated with a reactive organosilicon compound,
Photoelectron spectroscopy (ESCA), Auger electron spectroscopy (Au)
ger), secondary ion mass spectrometry (SIMS), and diffuse reflection FI-IR.

The amount of the reactive organosilicon compound used for the surface treatment is 0 for the reactive organosilicon compound based on 100 parts by mass of titanium oxide treated with the metal oxide in the charged amount at the time of the surface treatment. 1 to 50 parts by mass, more preferably 1 to 10 parts by mass. When the amount of surface treatment is less than the above range, the surface treatment effect is not sufficiently imparted, and the dispersibility of titanium oxide particles in the intermediate layer deteriorates.
Further, if it exceeds the above range, the electric performance is deteriorated, and as a result, the residual potential increases and the charging potential decreases.

As the reactive organosilicon compound used in the present invention, an organosilicon compound represented by the following general formula (1) is used.

General formula (1) R-Si- (X) _{3 In the} formula, R is an alkyl group, an aryl group, X is a methoxy group,
Represents an ethoxy group and a halogen atom.

In the organic silicon compound represented by the general formula (1), an organic silicon compound in which R is an alkyl group having 4 to 8 carbon atoms is more preferable, and a specific preferable example of the compound is trimethoxy. Examples thereof include n-butylsilane, trimethoxy i-butylsilane, trimethoxyhexylsilane, and trimethoxyoctylsilane.

As a preferred reactive organosilicon compound used for the final surface treatment in a plurality of surface treatments, a hydrogen polysiloxane compound can be mentioned. The hydrogen polysiloxane compound having a molecular weight of 1,000 to 20,000 is generally easily available,
Moreover, the black spot prevention function is also good. In particular, when methylhydrogenpolysiloxane is used for the final surface treatment, good effects can be obtained.

Another one of the surface treatments of titanium oxide of the present invention is titanium oxide particles surface-treated with an organic silicon compound having a fluorine atom. It is preferable to carry out the surface treatment with the organosilicon compound having a fluorine atom and the above-mentioned wet method.

That is, the organosilicon compound having a fluorine atom is dissolved or suspended in an organic solvent or water, untreated titanium oxide is added thereto, and such a solution is stirred for about several minutes to 1 hour. Then, the mixture is mixed, and if necessary subjected to heat treatment, dried through a step such as filtration to coat the titanium oxide surface with an organosilicon compound having a fluorine atom. The organosilicon compound having a fluorine atom may be added to a suspension prepared by dispersing titanium oxide in an organic solvent or water.

The fact that the titanium oxide surface is coated with an organic silicon compound having a fluorine atom means that
Photoelectron spectroscopy (ESCA), Auger electron spectroscopy (Au)
ger), secondary ion mass spectrometry (SIMS), and diffuse reflection FI-IR.

Examples of the fluorine-containing organic silicon compound used in the present invention include 3,3,4,4,5,5,5.
6,6,6-nonafluorohexyltrichlorosilane,
3,3,3-trifluoropropyltrimethoxysilane, methyl-3,3,3-trifluoropropyldichlorosilane, dimethoxymethyl-3,3,3-trifluoropropylsilane, 3,3,4,4,5 , 5, 6, 6,
6-nonafluorohexyl methyl dichlorosilane etc. are mentioned.

In the present invention, the surface treatment finally performed on the above N-type semiconductor particles includes a treatment using a reactive organic titanium compound or a reactive organic zirconium compound. The method is carried out by a method similar to the surface treatment method with the above reactive organosilicon compound.

The fact that the surface of the N-type semiconductor particles is coated with the reactive organic titanium compound or the reactive organic zirconium compound means that the surface is covered with photoelectron spectroscopy (ESCA),
It is confirmed with high accuracy by using a combination of surface analysis methods such as Auger electron spectroscopy (Auger), secondary ion mass spectrometry (SIMS), and diffuse reflection FI-IR.

Next, the surface-treated titanium oxide particles and other N-type semiconductor particles (hereinafter also referred to as surface-treated N-type semiconductor particles. In particular, the surface-treated titanium oxide particles are surface-treated. The structure of the intermediate layer using titanium oxide) will be described.

The intermediate layer of the present invention is a conductive support containing a liquid in which surface-treated N-type semiconductor particles such as surface-treated titanium oxide obtained by performing the surface treatment a plurality of times are dispersed in a solvent together with a binder resin. It is prepared by coating on top.

The intermediate layer is preferably an insulating layer, and the insulating layer has a volume resistance of 1 × 10 ⁸ to 10 ¹⁵
Ω · cm. Therefore, the volume resistance of the intermediate layer of the present invention is preferably 1 × 10 ⁹ to 10 ¹⁴ Ω · cm, more preferably 2 × 10 ⁹ to 1 × 10 ¹³ Ω · cm. The volume resistance can be measured as follows.

Measurement conditions: JIS: C2318-1975
According to. Measuring instrument: Hiresta IP manufactured by Mitsubishi Petrochemical Co., Ltd. Measuring condition: Measuring probe HRS Applied voltage: 500 V Measuring environment: 20 ± 2 ° C., 65 ± 5 RH% When the volume resistance is less than 1 × 10 ⁸ , the charge blocking property of the intermediate layer decreases. However, the generation of black spots increases and the potential holding property of the electrophotographic photosensitive member also deteriorates, so that good image quality cannot be obtained. On the other hand, if it is larger than 10 ¹⁵ Ω · cm, the residual potential is likely to increase due to repeated image formation, and good image quality cannot be obtained.

The intermediate layer of the present invention is provided between the conductive support and the photosensitive layer, and has good adhesion between the conductive support and the photosensitive layer and good electron injection from the photosensitive layer to the conductive support. , Mobility, and a barrier function of preventing hole injection from the support.

As the binder resin for the intermediate layer, polyamide resin, vinyl chloride resin, vinyl acetate resin, polyvinyl acetal resin, polyvinyl butyral resin, polyvinyl alcohol resin, melamine resin, epoxy resin,
Examples include thermosetting resins such as alkyd resins and copolymer resins containing two or more of the repeating units of these resins. Among these binder resins, a polyamide resin is particularly preferable, and an alcohol-soluble polyamide such as copolymerized or methoxymethylolated is particularly preferable. The amount of the surface-treated N-type semiconductor particles of the present invention dispersed in the binder resin is, for example, in the case of surface-treated titanium oxide, 10 to 10,000 parts by mass, preferably 50 parts by mass, relative to 100 parts by mass of the binder resin. To 1,000 parts by mass. By using the surface-treated titanium oxide in this range, the dispersibility of the titanium oxide can be kept good, and a good intermediate layer without black spots can be formed.

The thickness of the intermediate layer of the present invention is 0.5 to 15 μm.
Is preferred. By using the film thickness within the above range, it is possible to form an intermediate layer having good electrophotographic characteristics without causing black spots.

The coating solution for the intermediate layer prepared to form the intermediate layer of the present invention is a surface-treated N such as the surface-treated titanium oxide.
Although it is composed of mold semiconductor particles, a binder resin, a dispersion solvent, and the like, as the dispersion solvent, the same solvent as that used in the production of other photosensitive layers is appropriately used.

That is, the solvent or dispersion medium used for forming the intermediate layer, photosensitive layer and other resin layers of the present invention is n-
Butylamine, diethylamine, ethylenediamine, isopropanolamine, triethanolamine, triethylenediamine, N, N-dimethylformamide, acetone, methylethylketone, methylisopropylketone, cyclohexanone, benzene, toluene, xylene, chloroform, dichloromethane, 1,2-dichloroethane, 1 , 2-dichloropropane, 1,1,2-trichloroethane, 1,1,1-trichloroethane, trichloroethylene, tetrachloroethane, tetrahydrofuran, dioxolane, dioxane, methanol, ethanol, butanol, isopropanol, ethyl acetate, butyl acetate, dimethyl sulfoxide, Methyl cellosolve and the like can be mentioned. Among these solvents, the environmental load is small,
Non-halogen solvents are preferred.

The solvent for the coating liquid for the intermediate layer is not limited to these, but methanol, ethanol, butanol, 1-propanol, isopropanol and the like are preferably used. Further, these solvents can be used alone or as a mixed solvent of two or more kinds.

As the solvent for coating the intermediate layer, it is preferable to use a mixed solvent of methanol and a linear alcohol having high resin solubility in order to prevent uneven drying during coating of the intermediate layer. The ratio of the linear alcohol to the methanol is 1 to 0.05 by volume.
A mixture of 6 is preferable. By using the coating solvent as a mixed solvent in this way, the evaporation rate of the solvent can be appropriately maintained, and the occurrence of image defects due to uneven drying during coating can be suppressed.

As a dispersing means for the surface-treated titanium oxide used for preparing the coating solution for the intermediate layer, any dispersing means such as a sand mill, a ball mill or ultrasonic dispersing may be used.

As the coating processing method for producing the electrophotographic photosensitive member of the present invention including the intermediate layer, dip coating,
Although coating processing methods such as spray coating and circular amount regulation type coating are used, the coating processing on the upper layer side of the photosensitive layer does not dissolve the lower layer film as much as possible, and in order to achieve uniform coating processing, spray coating or circular coating It is preferable to use a coating processing method such as regulated coating (a circular slide hopper is a typical example). Regarding the spray coating, for example, JP-A-3-
No. 90250 and JP-A-3-269238, and the circular amount control type coating is described in detail, for example, in JP-A-58-189061.

Next, the constitution of the photoconductor preferably used in the present invention will be described. Conductive Substrate (Conductive Support) As the conductive support used in the photoconductor of the present invention, either a sheet shape or a cylindrical shape may be used, but in order to design the image forming apparatus compactly, the cylindrical shape is used. A conductive support is preferred.

The cylindrical conductive support of the present invention means a cylindrical support required to be able to form an image endlessly by rotating, and has a straightness of 0.1 mm or less and a shake of 0.1 mm or less. Conductive supports in the range are preferred. If the straightness and the shake range are exceeded, good image formation becomes difficult.

As the conductive material, a metal drum of aluminum, nickel or the like, a plastic drum on which aluminum, tin oxide, indium oxide or the like is deposited, or a paper / plastic drum coated with a conductive substance can be used. It is preferable that the conductive support has a specific resistance of 10 ³ Ωcm or less at room temperature.

The preferable photosensitive layer constitution of the electrophotographic photosensitive member of the present invention will be described below. Photosensitive Layer The photosensitive layer structure of the photoreceptor of the present invention may be a single-layer photosensitive layer structure in which one layer has a charge generation function and a charge transport function on the undercoat layer, but more preferably the photosensitive layer It is preferable that the function is divided into a charge generation layer (CGL) and a charge transport layer (CTL). By adopting a constitution in which the functions are separated, the increase in residual potential due to repeated use can be controlled to be small, and other electrophotographic characteristics can be easily controlled according to the purpose. In the negative charging photoreceptor, it is preferable that a charge generation layer (CGL) is formed on the undercoat layer and a charge transport layer (CTL) is formed on the charge generation layer. In the case of the photoconductor for positive charging, the order of the layers is the reverse of that of the photoconductor for negative charging. The most preferable photosensitive layer structure of the present invention is a negative charging photosensitive member structure having the function separation structure.

The constitution of the photosensitive layer of the function-separated negative charging photoreceptor will be described below. Charge Generation Layer The charge generation layer contains one or more charge generation materials (CGM). If necessary, a binder resin and other additives may be contained as other substances.

As the charge generating substance (CGM), a known charge generating substance (CGM) can be used. For example, a phthalocyanine pigment, an azo pigment, a perylene pigment, an azurenium pigment or the like can be used. Among these, CGM that can minimize the increase in residual potential with repeated use
Has a steric structure and a potential structure capable of forming a stable aggregation structure among a plurality of molecules, and specific examples thereof include a phthalocyanine pigment and a perylene pigment CGM having a specific crystal structure. For example, the Bragg angle 2θ with respect to Cu-Kα rays
CGMs such as titanyl phthalocyanine, which has a maximum peak at 27.2 °, and benzimidazole perylene, which has a maximum peak at 22.4, have almost no deterioration due to repeated use, and the increase in residual potential can be reduced. .

When a binder is used as a CGM dispersion medium in the charge generation layer, a known resin can be used as the binder, but the most preferable resin is formal resin, butyral resin, silicon resin, silicon modified butyral resin, phenoxy resin. Resin etc. are mentioned. The ratio of the binder resin to the charge generating substance is preferably 20 to 600 parts by mass with respect to 100 parts by mass of the binder resin.
By using these resins, the increase in residual potential due to repeated use can be minimized. The thickness of the charge generation layer is preferably 0.01 μm to 2 μm.

Charge Transport Layer The charge transport layer contains a charge transport material (CTM) and a binder resin for dispersing CTM to form a film. Other substances may optionally contain additives such as antioxidants.

As the charge transport material (CTM), a known charge transport material (CTM) can be used. For example, a triphenylamine derivative, a hydrazone compound, a styryl compound, a benzidine compound, a butadiene compound or the like can be used. These charge transport materials are usually dissolved in a suitable binder resin to form a layer. Among these, CTM that can minimize the increase in residual potential due to repeated use has high mobility and has a characteristic that the difference in ionization potential with CGM to be combined is 0.5 (eV) or less, and preferably 0. It is 0.25 (eV) or less.

The ionization potentials of CGM and CTM are measured by a surface analyzer AC-1 (manufactured by Riken Keiki Co., Ltd.).

Examples of the resin used for the charge transport layer (CTL) include polystyrene, acrylic resin, methacrylic resin, vinyl chloride resin, vinyl acetate resin, polyvinyl butyral resin, epoxy resin, polyurethane resin, phenol resin, polyester resin, alkyd. Resins, polycarbonate resins, silicone resins, melamine resins, and copolymer resins containing two or more of the repeating units of these resins. In addition to these insulating resins, poly-N
-Polymer organic semiconductors such as vinylcarbazole.

The most preferable binder for these CTLs is a polycarbonate resin. Polycarbonate resin is most preferable in simultaneously improving abrasion resistance, CTM dispersibility, and electrophotographic characteristics. The ratio of the binder resin to the charge transport material is the binder resin 1
10 to 200 parts by mass is preferable with respect to 00 parts by mass. or,
The thickness of the charge transport layer is preferably 10 to 40 μm.

Although the most preferable layer constitution of the photoconductor of the present invention has been described above, the photoconductor layer constitution other than the above may be used in the present invention.

In addition, in the image forming apparatus of the present invention,
A method of developing a latent image by supplying a thinned non-magnetic toner to the surface of the electrostatic latent image forming body is also preferable.

The image forming apparatus of the present invention comprises a toner conveying member, a toner layer regulating member and a toner replenishing auxiliary member,
Further, it is preferable that the toner replenishment assisting member and the toner conveying member are in contact with each other, and the toner layer regulating member and the toner conveying member are in contact with each other.

The toner conveying member supplies non-magnetic toner to the electrophotographic photosensitive member, and as the member, a member having elasticity is used from the viewpoint of ensuring a sufficient developing area while being in contact with the photosensitive member. preferable.

In the present invention, as the toner conveying member, a urethane rubber or silicone rubber roller or a conductive endless belt-like member (specifically, nickel or a PET base surface coated with a conductive material) is used. Those containing a sponge roller inside are preferably used.

The toner layer regulating member has a function of uniformly applying toner to the toner conveying member and imparting triboelectric charging, and specifically, an elastic body such as urethane rubber or a metal plate is used. The toner layer regulating member is brought into contact with the toner conveying member to form a thin layer of toner on the toner conveying member. The thin layer of toner is a layer in which a maximum of 10 layers of toner, preferably 5 layers or less, are formed in the developing area.

In the present invention, the toner layer regulating member is 100 mN / cm to 5 N / cm with respect to the toner conveying member from the viewpoint of preventing the conveyance unevenness due to the uniform toner conveyance and the occurrence of white streaks on the image. It is preferable that they are brought into contact with each other at a pressure of cm, and more preferably from 200 mN / cm to
It is 4 N / cm.

The toner replenishing auxiliary member is a unit for stably supplying the toner to the toner conveying member. As this, a water wheel-shaped roller with a stirring blade or a sponge-shaped roller can be used. In the present invention, from the viewpoint of stabilizing the toner supply and preventing the occurrence of streaky image defects, the toner replenishing member preferably has a diameter in the range of 0.2 to 1.5 times that of the toner conveying member. .

Next, one mode of the developing device (developing device) used in the image forming method of the present invention will be specifically described with reference to FIG.

FIG. 1 is a schematic sectional view of a developing device used in the image forming apparatus of the present invention. In FIG. 1, the non-magnetic one-component toner 16 contained in the toner tank 17 is forcibly conveyed and supplied onto the sponge roller 14 also serving as a toner replenishing auxiliary member by the stirring blade 15 serving as a toner replenishing auxiliary member. The toner incorporated on the sponge roller 14 is conveyed to the rubber roller 12 as a toner conveying member by the rotation of the sponge roller 14 in the arrow direction,
By friction with the rubber roller 12, it is electrostatically and physically adsorbed on the surface. On the other hand, the toner thus adhered on the rubber roller 12 is uniformly thinned by the rotation of the rubber roller 12 in the direction of the arrow and the elastic blade 13 made of steel as a toner layer thickness regulating member and is frictionally charged.

The toner thin layer thus formed on the rubber roller 12 develops a latent image by contacting or approaching the surface of the electrophotographic photosensitive drum (photosensitive member) 11 as an electrostatic latent image bearing member. The developing device used in the image forming method of the present invention is not limited to that shown in FIG.

As the fixing method used in the present invention, a so-called contact heating method is mentioned as a preferable fixing method. In particular, as the contact heating method, a heat pressure fixing method, a heat roller fixing method, and a pressure contact heating fixing method in which fixing is performed by a rotating pressure member containing a fixedly arranged heating body can be mentioned.

In the heat roll fixing method, in many cases, the heat source is provided inside a metal cylinder made of iron or aluminum whose surface is coated with tetrafluoroethylene or polytetrafluoroethylene-perfluoroalkoxyvinyl ether copolymers. It is composed of an upper roller and a lower roller made of silicone rubber or the like. As a heat source, it has a linear heater and the surface temperature of the upper roller is 12
A typical example is heating to about 0 to 200 ° C. In the fixing section, pressure is applied between the upper roller and the lower roller to deform the lower roller and form a so-called nip. The nip width is 1 to 10 mm, preferably 1.5 to 7 mm. The fixing linear velocity is 40 mm / sec to 600 mm / sec
Is preferred. When the nip is narrow, heat cannot be uniformly applied to the toner, resulting in uneven fixing.
On the other hand, when the nip width is wide, melting of the resin is promoted,
This causes a problem of excessive fixing offset.

Further, the image forming apparatus used in the present invention is preferably provided with a fixing cleaning mechanism. As the fixing cleaning mechanism, a method of supplying silicone oil to the upper roller or film for fixing, or a method of cleaning with a pad, roller, web or the like impregnated with silicone oil can be used. Further, in the present invention, a method of fixing by a rotating pressure member containing a fixedly arranged heating element can also be preferably used.

This fixing system is a system in which a heating member fixedly arranged and a pressure member which is in pressure contact with the heating member and is in close contact with the heating member to bring the recording material into close contact with the heating member are heated and fixed by pressure. The fixing device used for pressure contact heat fixing is
The heating element has a smaller heat capacity than a conventional heating roller and has a linear heating part in a direction perpendicular to the passing direction of the recording material. Usually, the maximum temperature of the heating part is 100 to 300 ° C.
Is preferably adjusted to

The image forming apparatus of the present invention preferably has a toner recycling mechanism.

Hereinafter, one mode of the toner recycling device will be described with reference to FIG. In the figure, 21 is a developing device, 22 is a developer carrying sleeve, 23 is a developer carrying screw, 11 is an electrophotographic photosensitive drum (photoconductor), 25 is a cleaner part, 26 is a cleaning member (elastic blade), and 27 is The recycled toner recovery screw and 28 are recycled toner conveying screws.

In FIG. 2, the transfer residual toner scraped off by the cleaning member 26 is conveyed from the cleaner section by the recycled toner recovery screw 27, and again supplied to the developing device 21 by the recycled toner conveying screw 28.

The toner recycling mechanism used in the present invention is not limited to that shown in FIG. As the toner recycling method, in addition to the above, the toner that has been developed on the photoconductor and remains on the photoconductor without being transferred to paper is collected by a blade or the like,
A method of conveying to a developing device can be used. The toner may be directly returned to the developing device, or a system in which the replenishment toner and the recycled toner are mixed in advance in an intermediate tank or the like and then supplied to the developing device may be used.

An example of the image forming apparatus used in the present invention is shown using a color electrophotographic image forming apparatus as shown in FIG.

FIG. 3 is a schematic block diagram showing an example of a color image forming apparatus used in the present invention.

The first, second, third and fourth image forming portions Pa, Pb, Pc and Pd are provided in the main body of the color image forming apparatus.
Are installed in parallel. Each image forming unit has the same configuration,
A visible image (toner image) of a different color is formed.

The image forming portions Pa, Pb, Pc and Pd are
Dedicated electrophotographic photosensitive drums 1a, 1b, 1c, respectively
And 1d. The images on the electrophotographic photosensitive drums (may be abbreviated as photosensitive drums) 1a, 1b, 1c, and 1d formed by the image forming portions Pa, Pb, Pc, and Pd are adjacent to the image forming portions. The image is transferred onto a recording material (also referred to as a transfer material) which is carried and conveyed on the recording material carrier 18 which moves. Further, the image on the recording material is heated and pressed by the fixing unit (fixing device) 10 to be fixed, and the recording material is discharged to the tray 61.

Next, the latent image forming section in each image forming section will be described. Photoconductor drums 1a, 1b, 1c, 1d
The static elimination exposure lamps 21a, 21b, 21
c, 21d, drum chargers 2a, 2b, 2c, 2d, a laser beam exposure device 17a as image exposure means, and potential sensors 22a, 22b, 22c, 22d. The photoconductor drums 1a, 1b, 1c, 1d that have been discharged by the discharge exposure lamps 21a, 21b, 21c, 21d.
Are uniformly charged by the drum chargers 2a, 2b, 2c, 2d, and then exposed by the laser beam exposure device 17a, so that the photosensitive drums 1a, 1b, 1
On c and 1d, a color-separated electrostatic latent image corresponding to the image signal is formed. In the image forming apparatus of the present invention, in addition to the above-described laser beam exposure apparatus 17a, as the image exposure means, there is a plurality of light levels other than OFF in the basic image unit (pixel) such as an LED array exposure apparatus. A well-known multi-value exposure means capable of irradiating the light can be preferably adopted.

The electrostatic latent image on the photosensitive drum is developed into a visible image by developing means. In other words, the developing means
Developers 3a, 3b, 3 filled with predetermined amounts of cyan, magenta, yellow, and black developers, respectively.
c, 3d, and the photosensitive drums 1a, 1b,
The electrostatic latent images formed on 1c and 1d are developed to form a visible image (toner image).

Next, the transfer section will be described. The recording material 6 held in the recording material cassette 60 is fed to the recording material carrier 18 via the registration rollers.

When the recording material carrier 18 starts to rotate,
The recording material is conveyed from the registration rollers onto the recording material carrier 18. At this time, the image writing signal is turned on, and the first electrophotographic photosensitive drum 1a is turned on at an appropriate timing.
An image is formed on it.

A transfer charger 4a and a transfer pressing member 41a are provided below the first electrophotographic photosensitive drum 1a, and a uniform pressing force is applied to the photosensitive drum by the transfer pressing member 41a. Then, the transfer charger 4a applies an electric field to transfer the toner image on the photosensitive drum 1a onto the recording material. At this time, the recording material is the recording material carrier 1.
The recording material is held by the electrostatic attraction force on the recording material 8, and the recording material is conveyed to the second image forming portion Pb, and the next transfer is performed. Hereinafter, the third and fourth image forming portions Pc, P are formed by the same method as described above.
The recording material on which the toner image formed by d is transferred is
The charge is removed by the separation charging device (separation electrode) 9, is separated from the recording material carrier 18 by the attenuation of the electrostatic attraction force, and is conveyed to the fixing unit (fixing device) 10.

The fixing section 10 includes heat-resistant cleaning members 73 and 74 for cleaning the fixing roller 71, the pressure roller 72, the rollers 71 and 72, and the rollers 71 and 7, respectively.
It is composed of heaters 75 and 76 for heating 2, a release agent oil 77 for applying a release agent oil such as dimethyl silicone to the fixing roller 71, an oil sump 78 for supplying the oil, and a thermistor 79 for controlling the fixing temperature. ing.

After the transfer, the photosensitive drums la, lb, lc,
Toner and the like remaining on the Id are removed from the photoconductor cleaning unit 5
a, 5b, 5c, 5d are removed to prepare for the subsequent latent image formation. Further, the toner and the like remaining on the recording material carrying member 18 are removed by the belt charge eliminator to remove the electrostatic attraction force, and then removed by the cleaning device 62 having a nonwoven fabric in this example. As the cleaning device 62, a rotating fur brush, a blade, a device using these in combination, or the like is also used.

[0225]

The present invention will be described in detail below with reference to examples, but the present invention is not limited to these. In addition, "part" in the sentence
Represents "parts by mass".

<< Photoreceptor >><< Preparation of Dispersion >> Each intermediate layer dispersion was prepared as follows.

(Preparation of Intermediate Layer Dispersion Liquid 1) Polyamide resin CM8000 (manufactured by Toray) 1.0 part Titanium oxide SMT500SAS (manufactured by Teika; surface treatment is silica treatment, alumina treatment, and methylhydrogenpolysiloxane treatment) 3.0 parts Methanol 10 parts Dispersion was carried out by a batch method with a sand mill as a disperser for a dispersion time of 10 hours to prepare an intermediate layer dispersion liquid 1.

(Preparation of Intermediate Layer Dispersion Liquid 2) 1 part of polyamide resin CM8000 (manufactured by Toray) was added to 7 parts of methanol and 1-
An intermediate layer dispersion liquid 2 was prepared by adding 3 parts of propanol into a mixed solvent and dissolving them.

[0229]   (Preparation of Intermediate Layer Dispersion Liquid 3)   Zirconium chelate compound ZC-540 (Matsumoto Pharmaceutical Co., Ltd.) 200 parts   Silane coupling agent KBM-903 (Shin-Etsu Chemical Co., Ltd.) 100 parts   700 parts of methanol   300 parts of ethanol The above mixed solution was prepared to prepare an intermediate layer dispersion liquid 3.

<< Production of Photoreceptor >> Photoreceptor 1 The following intermediate layer coating solution 1 was prepared and applied onto a washed cylindrical aluminum substrate by a dip coating method to form an intermediate layer having a dry film thickness of 2 μm. The drying conditions for the intermediate layer were low-temperature drying and slow control to control Benard cells stably.
That is, first, after drying at 60 ° C. for 10 minutes, 40 ° C.
Further drying was carried out in 0 minutes.

<Intermediate Layer (UCL) Coating Liquid 1> The intermediate layer dispersion liquid 1 was diluted twice with the same mixed solvent, and allowed to stand overnight and then filtered (filter; Rigimesh filter manufactured by Nippon Pall Ltd. nominal filtration accuracy: 5). Micron, pressure; 50 kPa).

The following compositions were mixed and dispersed using a sand mill to prepare a charge generation layer coating solution. This coating solution is applied by a dip coating method to form a dry film thickness of 0.3 μm on the intermediate layer.
The charge generation layer of was formed.

<Charge Generating Layer (CGL) Coating Solution> Y-type oxytitanyl phthalocyanine (Cu-Kα characteristic X-ray has a maximum peak angle of 2θ of 27.3 of 27.3) 20 parts Polyvinyl butyral (# 6000-C, Denki Kagaku Kogyo Co., Ltd.) 10 parts t-butyl acetate 700 parts 4-methoxy-4-methyl-2-pentanone 300 parts The following compositions were mixed and dissolved to prepare a charge transport layer coating liquid. This coating solution was applied onto the charge generation layer by a dip coating method to form a charge transport layer having a film thickness of 24 μm, to prepare a photoconductor 1.

<Charge Transport Layer (CTL) Coating Liquid> Charge Transport Material [N- (4-methylphenyl) -N- {4- (β-phenylstyryl) phenyl} -p-toluidine] 75 parts Polycarbonate resin “Iupilon -Z300 "(manufactured by Mitsubishi Gas Chemical Co., Inc.) 100 parts THF / toluene (7/3 volume ratio) 750 parts Photoconductor 2 Instead of the intermediate layer dispersion 1 used in the production of the photosensitive body 1, the intermediate layer dispersion 2 was used. Photosensitive member 2 was prepared in the same manner as photosensitive member 1, except that the intermediate layer was used and the dry film thickness was 0.5 μm.

Photoreceptor 3 Same as the photoreceptor 1 except that the intermediate layer dispersion 3 was used instead of the intermediate layer dispersion 1 used in the preparation of the photoreceptor 1, and the intermediate layer dry film thickness was 0.5 μm. To prepare the photoconductors 3, respectively.

Photoreceptor 4 A photoreceptor 4 was prepared in the same manner as the photoreceptor 1, except that a cylindrical aluminum substrate subjected to anodizing and sealing treatment was used as the substrate.

Evaluation 1 (Evaluation of Generation of Intermediate Layer Benard Cell Structure) After coating and drying the intermediate layer of the photoreceptor, the surface of the intermediate layer was observed with a scanning electron microscope at a magnification of 200, as shown in FIG. It was confirmed that a concave portion of the shape, that is, a large number of polygons were formed in the front, rear, left and right (Benard cell structure), and the following judgment was made. In FIG. 4, a indicates a hexagonal concave portion, and b indicates a spot-shaped concave portion.

⊚: Polygonal depressions having a maximum length of 20 to 200 μm are formed in 50% or more of the intermediate surface layer. ○: Polygonal depressions having a maximum length of 20 to 200 μm are 10 to 10 of the intermediate surface layer. 49% generation x: Polygonal recesses having the longest length of 20 to 200 μm were generated less than 10% of the intermediate surface layer or not generated at all, and the results are shown in Table 1.

[0239]

[Table 1]

<< Developer >><< Manufacture of Latex 1 >> A 5000 ml separable flask equipped with a stirrer, a temperature sensor, a cooling tube, and a nitrogen introducing device is previously charged with an anionic activator (sodium dodecylbenzenesulfonate: SDS). A solution prepared by dissolving 08 g of deionized water (2760 g) is added. While stirring at a stirring speed of 230 rpm under a nitrogen stream, the internal temperature is 80
The temperature was raised to ° C. On the other hand, 72.0 g of Exemplified Compound 19) was added to 115.1 g of styrene and 42.
A monomer solution was prepared by adding 0 g of methacrylic acid and 10.9 g of methacrylic acid, and heating the mixture to 80 ° C. to dissolve it. Here, the above heating solution was mixed and dispersed by a mechanical disperser having a circulation path to prepare emulsified particles having a uniform dispersed particle diameter. Then, a solution prepared by dissolving 0.84 g of a polymerization initiator (potassium persulfate: KPS) in 200 g of ion-exchanged water was added, and heated and stirred at 80 ° C. for 3 hours to prepare latex particles. Subsequently, a solution prepared by dissolving 7.73 g of a polymerization initiator (KPS) in 240 ml of ion-exchanged water was added, and 15 minutes later, 383.6 g of styrene, 140.0 g of n-butyl acrylate at 80 ° C.
A mixed solution of 36.4 g of methacrylic acid and 14.0 g of n-octyl-3-mercaptopropionic acid ester was added dropwise over 120 minutes. After heating and stirring for 60 minutes after completion of dropping, 4
After cooling to 0 ° C., latex particles were obtained.

Let these latex particles be latex 1. << Production of Colored Particles >> (Production of Colored Particles 1Bk) Sodium n-dodecylsulfate = 9.2 g is dissolved with stirring in 160 ml of ion-exchanged water.
To this solution, 20 g of Legal 330R (carbon black manufactured by Cabot Corporation) was gradually added with stirring, and then dispersed using CLEARMIX. As a result of measuring the particle diameter of the above-mentioned dispersion liquid using an electrophoretic light scattering photometer ELS-800 manufactured by Otsuka Electronics Co., Ltd., the weight average diameter was 112 nm.
This dispersion is referred to as "colorant dispersion 1".

1250 g of the above-mentioned “latex 1”, 2000 ml of ion-exchanged water and “colorant dispersion 1” were attached to a temperature sensor, a cooling pipe, a nitrogen introducing device, and a stirring device.
Place in a 4-liter four-necked flask and stir. After adjusting the temperature to 30 ° C., a 5 mol / liter sodium hydroxide aqueous solution was added to this solution to adjust the pH to 10.0. Then, an aqueous solution prepared by dissolving 52.6 g of magnesium chloride hexahydrate in 72 ml of ion-exchanged water was added under stirring at 30 ° C. for 5 minutes. Then, after standing for 2 minutes, the temperature rise is started and the liquid temperature is raised to 90 ° C. in 5 minutes (temperature rise rate = 1.
2 ° C / min). In that state, change the particle size by Coulter Counter T
When measured by AII, when the volume average particle diameter reaches 4.3 μm, 115 g of sodium chloride is added to 700 ml of ion-exchanged water.
The aqueous solution dissolved in was added to stop the particle growth, and the mixture was continuously heated and stirred at a liquid temperature of 85 ° C. ± 2 ° C. for 8 hours,
Salt out / fuse. After that, 30 at 6 ℃ / min
Cool to ℃, add hydrochloric acid to adjust the pH to 2.0,
The stirring was stopped. The generated colored particles are filtered /
It was washed and then dried with warm air of 40 ° C. to obtain colored particles. This is designated as "colored particle 1Bk".

(Production of Colored Particle 1Y) In the production of colored particle 1Bk, C.I. I. Pigment Yellow 185 was used, and colored particles were obtained in the same manner. This is designated as "colored particle 1Y".

(Production of Colored Particles 1M) In the production of colored particles 1Bk, C.I. I. Pigment Red 122 was used, and colored particles were obtained in the same manner. This is designated as "colored particle 1M".

(Production of Colored Particles 1C) In the production of colored particles 1Bk, C.I. I. Pigment Blue 15: 3 was used, and similarly, colored particles were obtained. This is designated as "colored particle 1C".

(Colored Particles 2Bk, 3Bk, 4Bk and 5
Production of Bk) In the production of colored particles 1Bk, colored particles 2 were prepared in the same manner except that the production conditions shown in Table 2 were changed.
Bk to 5Bk were produced respectively.

(Production of Colored Particles 6Bk to 8Bk) In the production of the colored particles 1Bk, the production conditions set in Table 2 were set, and the particle growth was stopped when the volume average particle diameter reached 3.8 μm. To produce colored particles 6Bk to 8Bk, respectively.

(Production of Colored Particles 9Bk to 11Bk) In the production of colored particles 1Bk, the production conditions set in Table 2 were set, and the particle growth was stopped when the volume average particle diameter reached 5.5 μm. , Colored particles 9Bk to 11Bk, respectively
Was manufactured.

(Production of Colored Particles 12Bk and 13Bk) In the production of colored particles 1Bk, the volume average particle diameter is 1.5 μm.
The particle growth was stopped at the time point when m and 9.3 μm, and colored particles 12Bk to 13Bk were manufactured.

(Production of Colored Particles 4Y) In the production of colored particles 4Bk, C.I. I. Pigment Yellow 185 was used, and colored particles were obtained in the same manner. This is designated as "colored particle 4Y".

(Production of Colored Particles 4M) In the production of colored particles 4Bk, C.I. I. Pigment Red 122 was used, and colored particles were obtained in the same manner. This is designated as "colored particle 4M".

(Production of Colored Particles 4C) In the production of colored particles 4Bk, C.I. I. Pigment Blue 15: 3 was used, and similarly, colored particles were obtained. This is designated as "colored particle 4C".

Table 2 shows the production conditions of the colored particles, and Table 3 shows the physical properties of the obtained colored particles.

[0254]

[Table 2]

[0255]

[Table 3]

(Production of Toner Particles) Colored Particle 1 Obtained
Bk to 13Bk, colored particles 1Y, 1M, 1C, 4Y, 4
Hydrophobic silica (number average primary particle size =
1% by mass of 12 nm, hydrophobicity = 68 and hydrophobic titanium oxide (number average primary particle size = 20 nm, hydrophobicity = 6)
3) Add and mix with a Henschel mixer, toners 1Bk to 13Bk, toners 1Y to 1C, toners 4Y to 4
I got C.

The physical properties such as the shape and particle size of the toner were the same as the physical property data of the colored particles shown in Table 3.

(Production of Developer) A volume average particle diameter of 60 μm in which each of the above toner particles is coated with a silicone resin.
Of the ferrite carrier of 6% and a toner concentration of 6%, developers 1Bk to 13Bk, developers 1Y to 1C, and developer 4Y.
~ 4C were each manufactured.

Next, the photoreceptors 1 to 4 and the developer were combined as shown in Table 4 (Examples 1 to 10 and Comparative Examples 1 to 4), and images were formed using a Konica Sitios 7040 (digital copying machine). The formed images were compared and evaluated.

<< Evaluation of image quality >> The evaluation is 1 for a character image with a pixel ratio of 7%, a portrait photograph, a solid white image, and a solid black image.
The original image in / 4 equal parts was continuously copied onto A4 paper for 100,000 sheets and evaluated after the continuous copying was completed.

The judgment criteria for each evaluation are as follows. The results obtained are shown in Table 4. Fog: A solid white image was measured for absolute reflection density using RD-918 manufactured by Macbeth.

∘: 0.005 or less (good) O: Greater than 0.005 and less than 0.01 (no problem in practical use) × ... Gender: Judged by a thin line image, while sharpness was judged by a generation copy of the character "Dust" at Mincho type / 9.6 points. Copy the “Dust” character image for 10 generations and check whether it is legible or not.
The number of readable generations was judged by the average value of the visual judgment by human members.

◎ ・ ・ ・ 9th generation or more (good) ○ ・ ・ ・ 5th to 8th generation (no practical problems) × ・ ・ ・ 4th generation or less (practical problems) Halftone unevenness: Halftone image Concentration difference (ΔHD
= Maximum density-minimum density) ◎ ・ ・ ・ 0.05 or less (good) ○ ・ ・ ・ greater than 0.05 and less than 0.1 (no practical problem) × ... 0.1 or more ( There is a problem in practical use.) It was judged by the number of black spots having a major axis of 0.4 mm or more per A4 paper. The major axis of the black spot was measured with a microscope equipped with a video printer.

∘: 0.4 mm or more black spot frequency: all copied images are 3 / A4 or less ○ ... 0.4 mm or more black spot frequency: 4 / A4 or more, 19 pcs / A4 or less Occurrence of one or more sheets (at a level where there is no problem in practical use) × ... Black spot frequency of 0.4 mm or more: 20 pieces / one sheet or more in A4 or more (there is a problem in practical use) Edge film peeling After a continuous copy, the photoconductor The surface and the edge of the sheet were observed, and the presence or absence of peeling of the photosensitive layer from the edge was observed.

◯: No edge film peeling ×: Edge film peeling occurred Cleaning property After completion of continuous copying, further halftone (pixel ratio = 3
0%) 100 sheets continuously in low temperature and low humidity environment (10 ° C, 10%
(RH), the presence or absence of defective cleaning was visually determined, and rank evaluation as shown below was performed. still,
Blade cleaning was adopted as the cleaning method.

[0266] ○: No problem △: Minor cleaning failure occurred ×: cleaning failure occurred The results obtained are shown in Table 4.

[0267]

[Table 4]

From Table 4, it is clear that the combination of the photoconductor of the present invention (Example) and the developer has higher image quality and better cleaning property than the combination of Comparative Example. is there.

<< Evaluation of Color Difference >> As shown in Table 5, a combination of a developer group and a photoconductor (Example 11, Comparative Example 5) was used, and a color copying machine as shown in FIG. 3 was used. An evaluation was carried out. A Y / M / C / Bk developing device was arranged around the laminated photoconductor, and after developing each color on the photoconductor, each color was transferred onto a recording material (paper) to form a full-color image. A blade cleaning method was used for cleaning the photoconductor. As the fixing method, a pressure contact type heat fixing device was used.

Evaluation was made by using a document having a full-color pixel ratio of 25% in a high temperature and high humidity environment of 30 ° C./80% RH and 1000
After printing one sheet, the difference in chroma between the images on the first and 1000th sheets was evaluated by color difference. The color difference was evaluated by the following method.

That is, the color of the solid image portion of the secondary color (red, blue, green) in each image is "Ma".
cbeth Color-Eye 7000 ", and the color difference was calculated using the CMC (2: 1) color difference formula.

The smaller the color difference obtained by the CMC (2: 1) color difference formula, the smaller the change in color.
If the color difference is 5 or less, the change in the tint of the image is at an acceptable level. The results obtained are shown in Table 5.

[0273]

[Table 5]

From Table 5, it is clear that the combination of the photoconductor of the present invention (Example) and the developer has a very small color difference and a small halftone unevenness as compared with the combination of Comparative Example.

[0275]

According to the present invention, an image forming apparatus, an image forming method, and an electronic device used in the image forming apparatus which have high image quality, good cleaning property, and a small color difference between images at the initial stage of development and after running are provided. We were able to provide a photographic photoreceptor.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view of a developing device used in an image forming apparatus of the present invention.

FIG. 2 is a schematic view showing one embodiment of a toner recycling device used in the present invention.

FIG. 3 is a schematic sectional view showing an example of a color image forming apparatus used in the present invention.

FIG. 4 is a diagram showing a large number of polygons formed in front, back, left and right (Benard cell structure).

[Explanation of symbols]

11 Electrophotographic photoconductor drum (photoconductor) 12 rubber roller 13 Steel elastic blade 14 Sponge roller 15 stirring blades 16 Non-magnetic single component toner 17 Toner tank 21 Developing device 22 Developer Transport Sleeve 23 Developer Transport Screw 25 Cleaner section 26 Leaning member (elastic blade) 27 Recycled toner recovery screw 28 Recycled toner transport screw

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) G03G 21/00 318 (72) Inventor Shinichi Hamaguchi 1st Sakura-cho, Hino-shi, Tokyo Konica Stock Association In-house (72) inventor Hiroshi Yamazaki Hachioji, Tokyo, Ishikawa-cho, 2970 address Konica stock company in the F-term (reference) 2H005 AA01 AB06 CA04 EA05 2H068 AA21 AA43 AA45 AA48 BA58 BB28 CA06 CA29 CA33 CA60 FA30 2H134 GA01 GB02 HD02 JA02 JA11 KD08 KG07 KG08 KH01 KH17

Claims (20)

[Claims] 1. A latent image formed on an electrophotographic photoreceptor,
In an image forming apparatus in which the toner is developed with a developer containing a toner, visualized, transferred to a recording material, and the residual toner on the electrophotographic photosensitive member is removed by a cleaning unit, a 50% volume particle diameter of the toner ( The ratio (Dv50 / Dp50) of Dv50) to 50% number particle size (Dp50) is 1.0 to
1.15, cumulative 7 from the larger volume particle size of the toner
The ratio (Dv75 / Dp75) of the 5% volume particle size (Dv75) to the cumulative 75% number particle size (Dp75) from the larger one of the number particle size of the toner is 1.0 to 1.20,
In all the toner, the number of toner particles having a particle size of 0.7 × (Dp50) or less is 10% or less, and the electrophotographic photosensitive member has an intermediate layer between the conductive support and the photosensitive layer. The image forming apparatus is characterized in that the intermediate layer is an insulating layer containing N-type semiconductor particles and a binder and forming a Benard cell. 2. A 50% volume particle diameter (Dv5) of the toner.
0) is 2 μm to 8 μm.
The image forming apparatus according to item 1. 3. The image forming apparatus according to claim 1, wherein the toner is obtained from colored particles obtained by polymerizing at least a polymerizable monomer in an aqueous medium. 4. The image formation according to claim 1, wherein the toner is obtained from colored particles obtained by salting out / fusing at least resin particles in an aqueous medium. apparatus. 5. The image forming apparatus according to claim 1, wherein the toner is a styrene- (meth) acrylate resin. 6. The image forming apparatus according to claim 1, wherein the N-type semiconductor particles are metal oxide particles. 7. The image forming apparatus according to claim 6, wherein the metal oxide particles are titanium oxide particles. 8. The titanium oxide particles are subjected to a surface treatment a plurality of times, and the final surface treatment is a surface treatment with a reactive organosilicon compound.
The image forming apparatus according to item 1. 9. The image forming apparatus according to claim 8, wherein the reactive organosilicon compound is methylhydrogenpolysiloxane. 10. The image forming apparatus according to claim 8, wherein the reactive organosilicon compound is an organosilicon compound represented by the following general formula (1). General formula (1) R-Si- (X) ₃ (R is an alkyl group, an aryl group, X is a methoxy group, an ethoxy group, a halogen group.) 11. The R in the general formula (1) is an alkyl group having 4 to 8 carbon atoms.
The image forming apparatus according to item 1. 12. The surface treatment of at least one of the plurality of surface treatments is a surface treatment with one or more compounds selected from alumina, silica, and zirconia. The image forming apparatus according to claim 1. 13. The titanium oxide particles are obtained by subjecting the titanium oxide particles to a surface treatment with silica and / or alumina and then subjecting them to a surface treatment with a reactive organosilicon compound. The image forming apparatus according to claim 1. 14. The image forming apparatus according to claim 7, wherein the titanium oxide particles are surface-treated with an organic silicon compound having a fluorine atom. 15. The image forming apparatus according to claim 1, wherein the N-type semiconductor particles have a number average primary particle diameter of 10 nm or more and 200 nm or less. 16. The image forming apparatus according to claim 1, wherein the film thickness of the intermediate layer of the electrophotographic photosensitive member is 0.2 to 15 μm. 17. The image forming apparatus according to claim 1, wherein the binder of the intermediate layer is a polyamide resin. 18. The image forming apparatus according to claim 1, wherein the cleaning unit has a polyurethane clinching blade. 19. An image forming method using the image forming apparatus according to claim 1. Description: 20. The electrophotographic photosensitive member used in the image forming apparatus according to claim 1, wherein the electrophotographic photosensitive member has an intermediate layer between the conductive support and the photosensitive layer. Is an insulating layer containing titanium oxide particles and a binder and forming a Benard cell, an electrophotographic photoreceptor.